Something that very few people know the true meaning of. Even though deja vu is French for "already seen", it actually is used to describe the strange feeling you get when you're in a situation, and feel like you've been in the exact same situation before, but really haven't. Most people think it means the same thing happening twice, which is wrong. Get it right people!

Jack: Hrmm..
Bob: What?
Jack: I could have sworn I've been here before. But I know I haven't.
Bob: Heh. Deja vu?
Jack. Yeah. What a strange feeling!

when one senses a feeling of reoccurance. when there is a feeling that you have already seen the whole scenario or scene that is surrounding you. sometimes these deja vu's occur in dreams. one may dream of something that at the time makes no sense but days, weeks, or months later, it happens and it all of a sudden hits you.

oh my goodness that's really freaky, i just had a deja vu. months ago i think of dreamt of exactly what just happened. she was wearing that, he replied to her comment and the same music was playing in the background